二层密度分层流体重力流的数值模拟

Numerical Simulation of Gravity Flows for Two-Layer Stratified Fluid

从RANS方程和RNGk-ε湍流模型出发,采用流体体积法(VOF)来模拟密度分层流动,对盐水和淡水因密度差异导致的分层重力流动现象进行了数值模拟。文中报道了平底水槽重力流、狭孔交换流的数值模拟结果,分层重力流锋面运动速度的计算值与现有的半理论半经验公式一致。为了揭示地形变化对分层重力流的影响,对设有缓变潜堤的水槽内分层重力流动的形成过程进行了数值模拟,给出了重力头推进速度和局部流场的计算结果,并讨论了分层流界面、流量和锋面附近的流速分布特征。

Based on RANS equations and RNG κ-ε turbulence model, the two-layer stratified gravity flow with the free surface in environmental flows was studied numerically. The VOF method was adopted to simulate the interface of the density stratified flows. The distributions of velocity interface level, flow rate and the position of gravity current head were provided. According to these numerical results, the velocity of gravity head with theoretical data and the experiments results available in the literature were compared. The feaures of stratification and turbulence were described reasonable by the models. The computational results agree well with the theoretical data and experimental results.